The present invention relates to a device and a method for converting movement patterns to control signals and, more particularly but not exclusively, to a device and a method for converting movement patterns to control signals using image processing.
The rapid miniaturization of complex electronic circuits and the emergence of high-resolution display devices have vastly increased the number and variety of portable processor based devices. Such portable processor based devices include handheld computers, mobile telephones, pagers and other portable communication and computing solutions. Moreover, the processing power, the data storage capability, the communication speed, and the battery life of portable processor based devices are continuing to develop at an accelerated pace.
Each one of the aforementioned portable processor based devices usually integrates a man machine interface (MMI) that allows a user to control its functioning. However, the MMI has to be adjusted to the small size of the portable autonomous device. The traditional MMI in such portable processor based devices is a miniaturized keyboard or a keypad which allows a user to input data having textual representation such as telephone number, a contact name, word processor content, etc.
Another MMI, which is typically used to input textual data in personal digital assistants (PDAs) is a touch screen. Such a device usually integrates a pen-like pointing device often stored next to or on the PDA. In use, the pen-like pointing device is applied to a touch screen on the PDA to enable a user to make choices and interact with the PDA device. High resolution LCD touch screens may be used in mobile phones and portable processor based devices. To determine where a display screen is touched, capacitive and resistive touch-sensitive layers are commonly used. They are based on transparent conductors such as indium-tin oxide films. However, the disadvantages in using such MMIs are their high price and limited transparency which reduces the picture quality, particularly of modern, high resolution LCD displays.
The aforementioned MMIs allow a user to control different functions of the related device by, inter alia, inputting a simple, short sign such as a character or pressing on a desired icon or letter on a simulated or real keyboard. Since each MMI is adjusted to the size of a miniaturized device, a user may have to concentrate in order to find the related small switch or to scribble the desired character using the pen-like pointing device. Furthermore, there is a limited ability to configure the MMI so that one action or key press produces a result or event due to physical constraints.
The rapid miniaturization of complex electronic circuits has recently led to the integration of image sensors into the portable processor based devices. PDAs, mobile phones, and laptops integrate cameras which are used to capture still and video images. One of the reasons for the prevalence of such products is the price and size reduction of image sensors such as complementary metal oxide semiconductor (CMOS) image sensors or charge coupled portable processor based devices (CCDs).
The integration of image sensors opens up additional possibilities to allow users to interface with portable processor based devices. Known camera integrated mobile phones, for example, use a motion interface engine which facilitates control of the device by, for example, inputting directional or movement instructions into the device via the image sensor to control functions such as scrolling through menus. However, these applications can only be used for navigation through different menus of the device or for controlling the display of an object viewer such as a cursor. The directional instructions cannot be used as a basis for inputting characters or other predefined signs which are usually input using a keypad or a keyboard. Moreover, inputs which are comprised of a sequence of directional instructions cannot be entered as a single instruction.
There is thus a widely recognized need for, and it would be highly advantageous to have, a device and a method for an MMI devoid of the above limitations.